Field
Exemplary embodiments of the present invention relate to a touch panel and a display device using the same. More particularly, exemplary embodiments of the present invention relate to a touch panel and a display device using the same that may prevent deterioration of a touch sensing capability.
Discussion of the Background
A display device, such as a liquid crystal display (LCD), an organic light emitting diode (OLED) display, and an electrophoretic display may include a field generating electrode and an electro-optical active layer. The liquid crystal display may include a liquid crystal layer as the electro-optical active layer, an organic light emitting diode display may include an organic emission layer as the electro-optical active layer, and an electrophoretic display may include charged particles. The field generating electrode may be connected to a switching element, such as a thin-film transistor, to receive a data signal, and the electro-optical active layer may convert the data signal to an optical signal to display an image.
A display device may include a touch sensing function through which a user may interact, in addition to an image displaying function. The touch sensing function may determine touch information such as whether an object approaches or touches a screen, a touch position thereof, and the like, by sensing a change in pressure, charges, light, and the like, which are applied onto the screen of the display device, when a user writes a text or draws a figure by approaching or touching the screen with a finger or a touch pen. The display device may receive an image signal based on the touch information to display an image.
The touch sensing function may be implemented by a touch sensor. The touch sensor may be classified into various types, such as a resistive type, a capacitive type, an electro-magnetic (EM) type, and an optical type.
Among the touch sensors, the capacitive type touch sensor includes a sensing capacitor including sensing electrodes that may transfer sensing signals and determine whether a touch exists, a touch position, and the like, by sensing a change in charge capacitance or a change in charged amount of the sensing capacitor generated when a conductor such as a finger approaches the touch sensor. The capacitive type touch sensor includes touch electrodes disposed in a touch sensing area and a touch signal line connected to the touch electrodes. The touch signal line may transfer a touch driving signal to the touch electrode or transfer a sensing output signal of the touch electrode generated, according to a touch to a sensing signal controller.
A touch sensor may be formed in the touch panel to be attached onto the display device (add-on cell type), outside the substrate of the display device (on-cell type), or inside the display device (in-cell type). A touch area may overlap a display area in the display device. Panels including the touch sensor may be referred to as touch panels. The touch panels may be a panel of the display device including the touch sensor, or may be a panel attached to the display device. Since a periphery of the touch area extends along a peripheral area, a touch signal line may be connected to the sensing signal controller.
When a user holds and uses a touch panel, the user may grip a peripheral area of the touch panel with the user's hand or other objects. At that time, when multi-hovering, a charge amount of the touch electrode may be decreased compared with a base capacitance of the touch panel, which may deteriorate a touch sensing capability in the touch area.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the inventive concept, and, therefore, it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.